title: I saw a celebrity on television running a marathon on a replaced knee joint.  Is it OK to do things like that on a replaced knee or hip?
mesh_terms: D006622:Hip Prosthesis / Q000009:adverse effects*; D006801:Humans; D007720:Knee Prosthesis / Q000009:adverse effects*; D010146:Pain / Q000209:etiology* / Q000517:prevention & control; D011475:Prosthesis Failure; D012307:Risk Factors; D040242:Risk Reduction Behavior; D012420:Running / Q000293:injuries*